Dictionary of National Biography, 1901 supplement/Blenkinsop, John

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BLENKINSOP, JOHN (1783–1831), one of the pioneers of the locomotive, was born near Leeds in 1783, and became the principal agent of the Brandling family who owned the extensive Middleton collieries in that district. On 10 April 1811 he obtained a patent (No. 3431) for a new species of locomotive, developing some of the ideas embodied in the locomotive constructed by Richard Trevithick [q. v.] in 1803, but combining with them a new plan to overcome the presumed difficulty of securing adhesion between the engine wheels and the rails. This was effected by means of a racked or toothed rail, laid along one side of the road, into which the toothed wheel of the locomotive worked as pinions work into a rack. The boiler of Blenkinsop's locomotive was of cast iron, of the plain cylindrical kind with one flue — the fire being at one end and the chimney at the other. It was supported upon a carriage resting without springs, directly upon two pairs of wheels and axles, which were unconnected with the working parts, and served merely to support the weight of the engine upon the rails, the progress being effected wholly by the cog-wheel working into the toothed rack. The engine had two cylinders instead of one as in Trevithick's engine. The invention of the double cylinder was due to Matthew Murray, of the firm of Teuton, Murray, & Wood, one of the best mechanical engineers of his time ; Blenkinsop, who was not himself a mechanic, having consulted him as to all the practical details. The connecting rods gave the motion to two pinions by cranks at right angles to each other ; these pinions communicating the motion to the wheel which worked into the cogged rail.

The first experiment with Blenkinsop's engine was made on Wednesday, 24 June 1812. Upon that day 'at 4 o'clock in the afternoon the machine ran from the coal staith to the top of Hunslet moor, where six and afterwards eight waggons of coal, each weighing 3¼ tons, were hooked to the back part. With this immense weight, to which, as it approached the town, was superadded about fifty of the spectators mounted upon the waggons, it set off on its return journey to the coal staith and performed the journey, a distance of about a mile and a half, in 23 minutes, without the slightest accident' (Leeds Mercury, 27 June 1812). The machine was stated to be capable, when lightly loaded, of moving at a speed of ten miles an hour. A drawing and description of it with the official specification were given in the 'Leeds Mercury' of 18 July 1812.

Blenkinsop's engine has an undoubted claim to be considered the first commercially successful engine employed upon any railway. The locomotives made upon the Blenkinsop pattern began working regularly in August 1812, hauling 30 coal wagons a distance of 3½ miles within the hour. They continued for many years to be thus employed and formed one of the chief curiosities of Leeds, being greatly admired by the Grand Duke (afterwards the czar) Nicholas in 1816. George Stephenson saw one of the 'Leeds engines' at Coxlodge on 2 Sept. 1813, and his first locomotive constructed at Killingworth was built to a large extent after the Blenkinsop pattern ; but he soon saw his way to get rid of the cog-wheels, and it was his second locomotive of 1815 which ranks as the direct ancestor of the present machine (cf. Robert Stephenson's Narrative of My Father's Inventions).

Blenkinsop died at Leeds on 22 Jan. 1831, 'after a tedious illness, aged forty-eight.' A beautiful model of his engine of 1812 was exhibited at a conversazione of the Leeds Philosophical Society in December 1803, and a photograph of this model with explanatory notes has since been placed in the Leeds Philosophical Hall.

[Leeds Mercury, 29 Jan. 1831; Taylor's Biograpbia Leodiensis, 1865, 327; Smiles's Lives of the Engineers, 1862, iii. 87, 97; Woodcroft's Index of Patentees, 1617–1852; Trevithick's Life of Richard Trevithick, 1872, 208; Stuart's Descriptive History and Anecdotes of the Steam Engine.]

T. S.